I had a 4" pvc drain pipe coupling left over from installing new drain pipe from the day before.
I just cut a notch for the cup handle, and a triangle shaped notch in the bottom so it fit against the handrail on the fender.
I painted it black and attached it with one screw into the side of the plastic lever housing. The lever housing has thick plastic areas for the fender screws, so I attached it in one of these areas.
I'll be trying it out tomorrow morning.
For the other side, I think I'll weld something up out of steel rod. Should look better and be fun to make.
Vic